Oct 24, 2012:
Using remote DNS such as Google DNS can result in poor web performance. Get the best of both worlds—the benefits of public DNS and the best web performance by installing namehelp today!

In a study to be presented at the Internet Measurement Conference in Boston this November, we show how remote DNS services (such as Google DNS or OpenDNS) can actually hurt your overall web performance by inadvertently directing you to download content from far-away servers. Internet Service Providers (ISPs) have traditionally provided DNS service via servers located in the ISP's own network—near to the users. Recently we have seen a growing trend of users switching to remote DNS services due to their speed, reliability and security features.

Using remote DNS can actually reduce your web performance due to a poor interaction with Content Delivery Networks (CDNs), which are commonly used by websites to (ironically) improve their performance. This is because CDNs try to direct users to a nearby server for downloading content based on the location of your DNS server. If your DNS server is far away from you (as is the case with remote DNS), you may not be directed to the nearest server, resulting in slower downloads. Our study finds that using remote DNS can double the time it takes to fetch content for 40% percent of users!

Relative end-to-end latency % difference(smaller is better)

CDF of measurement locations

Relative benefit of namehelp compared to Google DNS.

We have released a tool called namehelp that you can install today to address this issue and improve your web performance. It achieves this by directly contacting CDNs to determine a server near to you. The figure above shows that, for locations where using Google DNS adversely affects web performance, namehelp significantly improves performance compared to simply using Google DNS. For the average user, this translates to a 38% performance improvement!

On September 1, 2011, the New Zealand government put into effect the Copyright Infringing File Sharing Act, a three strike policy with penalities up to $15,000 and disconnection of service for illegally sharing copyrighted material online.

The plot below shows the number of unique BitTorrent users seen in New Zealand according to data reported by Ono users. In the days leading up to the enforcement of the bill, the maximum number of BitTorrent users seen throughout a day from New Zealand consistently peaks at approximately 1300 users seen in an hour. However, after September 1st, the daily maximum number of peers seen per hour does not surpass 1000, usually hovering around 750 peers. Furthermore, once the law is put into place, the number of peers seen per hour begins to dip below 500 during off-peak hours.

Time (UTC)

# of Peers seen

Number of peers seen online in New Zealand before and after the new copyright legistation is put into effect. The shaded region begins on September 1, 2011 at midnight UTC.

Several news sources (CNN, BBC) have reported that on November 1st, Palestine's networks were the target or cyber attacks. Here we examine how BitTorrent users were affected by these attacks and subsequent network outages. The graph below shows the number of BitTorrent users seen online per hour. We see a sharp drop of about 75% in the number of connected users in Palestine for a few hours, occurring between 1 am and 4 am (UTC) on November 1st. The drop begins around the same time the renesys blog reports a drop in reachable networks in Palestine.

Time (UTC)

# of Peers seen

Number of peers seen in Palestine between October 29th and November 3rd. The shaded region represents the day of the cyber attack. The dip in users on November 1st occurs at approximately the same time as what was reported on the renesys blog.